*{
  margin: 0;
  padding: 0;
}
li{
  list-style: none;
}
.background{
  width: 100%;
  height: 100%;
  position: fixed;
  background-image: url('http://visit.lening365.com/static/img/20220418203517.73d99f43.jpg');
  background-size: 100% 100%;
}
.box{
  width: 450px;
  height: 255px;
  position: absolute;
  top: 50%;
  left: 50%;
  margin-top: -300px;
  margin-left: -225px;
  .title{
    font-size:24px ;
    color: #eeeeee;
    text-align: center;
  }
  .username{
    width: 450px;
    height:50px ;
    background-color:#283443 ;
    margin-top: 45px;
    .account{
      width: 440px;
      height:50px ;
      border: none;
      margin-left: 10px;
      background-color: #283443;
      color:#ffffff ;
      outline: none;
    }
  }
   .pwd{
    width: 450px;
    height:50px ;
    background-color:#283443 ;
    margin-top: 20px;
    .password{
      width: 440px;
      height:50px ;
      border: none;
      margin-left: 10px;
      background-color: #283443;
      color:#ffffff ;
      outline: none;
    }
  }
  button{
    width:450px ;
    height:35px ;
    background-color: #1890ff;
    border: none;
    border-radius: 5px;
    margin-top: 20px;
    color: #ffffff;
    cursor: pointer;
  }
}